1. Field of the Invention
The present invention relates to a camera equipped with a photometric value compensation device that can superimpose photographic information in the finder field.
2. Description of Related Art
With a camera equipped with a line of vision detection device for detecting the line of vision of the photographer when the photographer looks into the finder, when the point of focus of the photographer is displayed, a mark 22 showing the point of focus is generally superimposed in the finder field 21, as shown in FIG. 2. With a camera in which (automatic focus) AF is possible in multiple locations, when an AF area is displayed during autofocus selection, a mark 23 showing the AF area is generally superimposed in the finder field 21 as shown in FIG. 2.
In FIGS. 3-5, an example of a superimposing display device and a photo metering method are shown for use in a single lens reflex camera. In FIG. 3, the subject light that has passed the photo lens 31 is reflected by the mirror 32 and focussed to an image on the screen 33. The subject image on the screen 33 is viewed by the photographer via the eyepiece lens 34, pentagonal prism 35, and condenser lens 36. As shown in FIG. 4, the light radiating elements 37 have light emitting components 39 such as LED's or the like positioned in the form of two-dimensional matrices, which partially illuminate the screen 33 via the pentagonal prism 35 and superimpose the pattern of mark 22 on the screen 33 at an established position. The two light radiating elements 37 are positioned at the left and right sides of the eyepiece lens 34 so as to shine light onto the left half and right half of the finder field, respectively. The finely divided photo metering device 38 measures the light of the subject image on the screen 33 through the pentagonal prism 35. The light from a light radiating element 37 reflected back to the photo metering device 38 increases the measured light intensity to a value higher than the value that would be due to the subject image alone.
FIG. 5 shows another example of a superimposed display, in which a variable transmission display device 40, such as an electronic element or a liquid crystal element, which can electrically change the amount of light transmitted, is positioned between the screen 33 and the condenser lens 36. On the variable transmission display device 40, a contrast is formed with the surrounding areas by decreasing the light transmission of the elements in the fixed coordinate position or positions by applying voltages to these elements, thereby displaying the pattern of mark 22. Therefore, the overall brightness decreases when voltages are applied to these elements. That is, the reduced transmission of the elements decreases the light intensity measured by the photo metering device 38 to a value lower than the value that would be due to the subject image alone.
When photo metering is accomplished with a single lens reflex camera, the photographic field is often divided into regions and so-called "finely divided photo metering" is accomplished. In order to carry out more accurate photo metering and to obtain a better exposure value, the number of divisions of the field can be increased. However, since the individual light measuring regions become smaller as the number of field divisions increase, in regions in which there is a superimposed mark or character, changes in the brightness or light transmission of the mark or character can influence the photometric value of the region in which the character exists.